Lying flat for 24 hours after a stroke is no better than sitting up at an angle of at least 30 degrees. These differences in early head position did not affect people’s levels of disability or survival to 90 days, which was more than 92% in both groups. It had been thought that the head down position might increase the chance of pneumonia, but in this trial, the rates were also similar for people cared for in either position.
The results of this large international randomised controlled trial are likely to be applicable to adults with different types of stroke in varied settings. As lying position did not affect outcomes, this suggests that clinicians can be guided by patients’ clinical condition, preferences and levels of comfort during the initial management of care.
The current NICE guideline on diagnosis and initial management of stroke suggests that people with acute stroke should be helped to sit up as soon as possible (when their clinical condition permits).
Why was this study needed?
A stroke occurs when the blood (and therefore oxygen) supply to part of the brain is cut off. Over 80,000 people in England and Wales are admitted to hospital with an acute stroke each year. Disability following stroke is very common: after six months, 40% of people have difficulty with basic self-care such as dressing and feeding.
The evidence about whether lying patients flat on their backs following stroke is better than sitting them up has been inconclusive. Lying horizontally with the face upwards may increase blood and oxygen flow to the brain. On the other hand, sitting up with the head raised may reduce both pressure on the brain in patients with large strokes, and the risk of aspiration pneumonia - a common complication following a stroke.
This study aimed to compare the effects of these positions, to help determine which one should be used in practice.
What did this study do?
The Head Positioning in Acute Stroke Trial (HeadPoST) included 11,093 adults with acute stroke from 114 hospitals in nine countries. This included 4,160 patients from 41 hospitals in the UK. Hospitals were randomised to have patients either lie horizontally or to sit up with their head elevated for 24 hours, starting as soon as possible after admission. Each hospital switched to using the other positioning after a specified number of patients had been treated.
This was a well-designed trial, with reliable results. Its findings are likely to be applicable in practice, as it included patients with different types of stroke, and the participating hospitals covered a range of settings (such as rural and urban, public and private).
What did it find?
- Head position did not significantly affect disability as assessed on the modified Rankin scale at 90 days (odds ratio [OR] for comparison of overall score distribution 1.01, 95% confidence interval [CI] 0.92 to 1.10). In the lying-flat group, 30.8% of the patients had major disability (not including death) at 90 days, compared to 31.4% of the patients in the sitting-up group.
- Head position also did not affect the risk of death within 90 days after stroke. In the lying-flat group, 7.3% of patients died compared to 7.4% in the sitting-up group (OR 0.98, 95% CI 0.85 to 1.14).
- There was no difference in the proportion of patients developing pneumonia between the groups: 3.1% in the lying-flat group versus 3.4% in the sitting-up group (OR 0.86, 95% CI 0.68 to 1.08).
- While lying flat improved overall health-related quality of life at 90 days, this effect was small (average 1.4 points on the 100 European Quality of Life Group 5-Dimension Self-Report Questionnaire [EQ-5D] visual analogue scale). There were no differences in quality of life in the five subdomains assessed - mobility, self-care, usual activities, pain and discomfort, or anxiety and depression.
- Patients in the lying-flat group were more likely to discontinue their assigned position: 13.1% stopped compared with 4.2% in the sitting-up group (OR 4.0, 95% CI 3.1 to 5.3). The most common reason was that they could not tolerate lying flat (28.9% of discontinuations).
What does current guidance say on this issue?
NICE’s 2008 guideline on the diagnosis and initial management of stroke in the over 16s has a section on early mobilisation and optimum positioning of people with acute stroke. It recommends that people who have experienced a stroke should be helped to sit up as soon as their clinical condition permits. It suggests that this will help to maintain blood oxygen levels and reduce the likelihood of pneumonia.
This guideline is due to have a partial update published in 2019.
What are the implications?
Current practice varies around positioning stroke patients during their early management. The results of this large, well-designed trial should be taken note of. It shows that lying flat has no important benefits over sitting up. This may mean that clinicians should be guided by patients’ clinical condition and preferences in this period.
The assigned head positions were adopted a median of 14 hours after stroke (interquartile range five to 35 hours), and it is possible that results might differ if they were adopted sooner. However, it may be difficult to achieve this in regular clinical practice.
This evidence might inform future updates to the NICE guideline, but is an area where patient and clinician choice can now be guided by “strong evidence of no difference”.
Citation and Funding
Anderson CS, Arima H, Lavados P, et al; HeadPoST Investigators and Coordinators. Cluster-Randomized, Crossover Trial of Head Positioning in Acute Stroke. N Engl J Med. 2017;376(25):2437-47
This project was funded by the National Health and Medical Research Council of Australia.
NHS Choices. Stroke. London: Department of Health; 2016.
NICE CKS. Stroke and TIA. London: National Institute for Health and Care Excellence Clinical Knowledge Summaries; 2017.
NICE. Stroke and transient ischaemic attack in over 16s: diagnosis and initial management. CG68. London: National Institute for Health and Care Excellence; 2008.
Produced by the University of Southampton and Bazian on behalf of NIHR through the NIHR Dissemination Centre